P0716

Circuit Description
The Automatic Transmission Input (shaft) Speed (A/T ISS) sensor provides transmission input speed to the Powertrain Control Module (PCM). The A/T Input Speed Sensor (ISS) is a Permanent Magnet (PM) generator. The sensor mounts into the transmission case and maintains a slight air gap between the sensor and the forward clutch housing. The PM generator produces an AC voltage as the forward clutch housing rotor teeth pass through the sensor's magnetic field. The AC voltage level increases as the turbine shaft speed increases. The PCM converts the AC voltage into a digital signal. The PCM determines actual turbine speed using the digital signal. The PCM uses the input speed to calculate torque converter slip speed, and gear ratios.

When the PCM detects an unrealistically large change in input speed, then DTC P0716 sets. DTC P0716 is a type B DTC.

Conditions for Running the DTC
^ No A/T ISS sensor DTC P0717.
^ No ISS sensor DTCs P0722 or P0723
^ No shift solenoid DTCs P0751 or P0753.
^ System voltage is 8.0-18.0 volts.
^ Engine speed is greater than 475 RPM.
^ The Accelerator Pedal Position (APP) angle is greater than 15%.
^ Transmission fluid pressure manual valve position switch is not indicating PARK or NEUTRAL.
^ The vehicle speed is greater than 32 Km/h (20 mph).

Conditions for Setting the DTC
The A/T ISS varies by more than 1200 RPM within 4 seconds.

Action Taken When the DTC Sets
^ The PCM illuminates the Malfunction Indicator Lamp (MIL).
^ The PCM commands maximum line pressure.
^ The PCM freezes shift adapts.
^ The PCM stores DTC P0716 in PCM history.

Conditions for Clearing the MIL/DTC
^ For Federal and California emissions, the PCM turns OFF the MIL during the third consecutive trip in which the diagnostic test runs and passes.
^ A scan tool clears the DTC from PCM history.
^ For Federal and California emissions, the PCM clears the DTC from PCM history if the vehicle completes 40 consecutive warm-up cycles without an emission related diagnostic fault occurring.
^ For vehicles equal to or greater than 15,000 lbs GVW, the PCM clears the DTC from PCM history if the vehicle completes 40 consecutive warm-up cycles without a non-emission related diagnostic fault occurring.
^ The PCM cancels the DTC default actions when the fault no longer exists and the ignition switch is OFF long enough in order to power down the PCM.

Diagnostic Aids
^ Inspect the wiring at the PCM, the transmission connector and all other circuit connecting points for the following conditions:
- A backed out terminal
- A damaged terminal
- Reduced terminal tension
- A chafed wire
- A broken wire inside the insulation
- Moisture intrusion
- Corrosion
^ When diagnosing for an intermittent short or open, massage the wiring harness while watching the test equipment for a change.
^ You may have to drive the vehicle in order to experience a fault.
^ First diagnose and clear any engine DTCs that are present. Then inspect for any transmission DTCs that may have reset.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
4. This step tests for proper operation of the A/T ISS sensor.
8. This step tests for proper A/T ISS sensor circuit operation up to the PCM connections. You remove the fuel solenoid fuse in order to eliminate a flooding condition during this step.
10. This step tests for a short to ground in the A/T ISS sensor circuit.